<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="http://code.jquery.com/jquery-2.1.1.min.js"></script>
</head>

<body>
    <script>
        $.ajax({
            url: '../data/1.json',
            success(res) {
                console.log(res)
                if (true) {
                    $.ajax({
                        url: '../data/2.json',
                        success(res) {
                            console.log(res)
                            if (true) {
                                $.ajax({
                                    url: '../data/3.json',
                                    success(res) {
                                        console.log(res)
                                        if (true) {
                                            $.ajax({
                                                url: '../data/1.json',
                                                success(res) {
                                                    console.log(res)
                                                    if (true) {
                                                        $.ajax({
                                                            url: '../data/2.json',
                                                            success(res) {
                                                                console.log(res)
                                                                if (true) {
                                                                    $.ajax({
                                                                        url: '../data/3.json',
                                                                        success(res) {
                                                                            console.log(res)
                                                                            if (true) {
                                                                                $.ajax({
                                                                                    url: '../data/1.json',
                                                                                    success(res) {
                                                                                        console.log(res)
                                                                                    }
                                                                                })
                                                                            }
                                                                        }
                                                                    })
                                                                }
                                                            }
                                                        })
                                                    }
                                                }
                                            })
                                        }
                                    }
                                })
                            }
                        }
                    })
                }
            }
        })
    </script>
</body>

</html>